What Luna worries about

Luna and I were at the grocery store, and Luna was in the infant seat on a grocery cart when a woman said to me, "She doesn't have a care in the world, does she?" Luna asked me what she said so I told her, "She said that you don't have anything to worry about." So I asked Luna, "What do you worry about?" and she said, "One time I was worried that Buddy (our dog) was going to mess up my mudballs."